1. Field of the Invention
This invention relates to a roll grinding apparatus for rolling mills, and more particularly to a roll grinding apparatus that dresses the profile of used work and back-up rolls of plate mills and pinch rolls of coilers by grinding in-line.
2. Description of the Prior Art
With a view to increasing the efficiency of rolling operation, several methods of grinding work and other rolls in line while the rolling operation is in progress have been proposed as in the Japanese Utility Model Gazette No. 45037 of 1974, Japanese Provisional Patent Publications Nos. 58951 of 1978, 3989 of 1979, 65061 of 1980 and 53806 of 1981.
Previously the inventor proposed a method of grinding rolling mill rolls which comprises reciprocating a grindstone pressed against the surface of a roll not only in the direction parallel to the axis of the roll but also in the direction in which the roll rotates (Japanese Provisional Patent Publication No. 14010 of 1981). By this method, the roll surface can be ground efficiently and precisely without causing grindstone blocking and abrasion. In this method, the roll surface is ground with a plurality of rectangular grindstones reciprocatively disposed along the roll axis. While being kept in close contact with the roll surface, the grindstones are driven in such a manner as to make a motion in which said two reciprocative movements are combined.
To grind the roll surface to a desired shape with precision machining on the order of .mu.m according to the method just described, it is necessary to press the individual grindstones against the roll surface with an appropriate amount of pressure and put the grindstones in exact working position with respect to the roll to be dressed. For increasing the operational efficiency, it is also necessary to rapidly place the grindstones in the desired position. So far, however, no combined grinding apparatus satisfying such requirements has been proposed.